Oh no, no, no... that's normal... The human brain has a nice portion of it dedicated to face recognition and that's the way the brain works. Even if there are no faces in the pictures, your brain will 'fill the gaps' and show you one in a few seconds. I find this very interesting because it shows how two different brains can see the same thing where there is nothing at all. But beware... only happens with faces... human faces. If you see something else you are breaking the rules...